Clinic of Infectious Diseases, Perugia General Hospital, Perugia, Italy.
Medical Microbiology, Department of Medicine, University of Perugia, 1, Piazzale Menghini, 06129, Perugia, Italy.
Eur J Clin Microbiol Infect Dis. 2018 Dec;37(12):2313-2322. doi: 10.1007/s10096-018-3377-5. Epub 2018 Sep 14.
The impact on time to results (TTR) and clinical decisions was evaluated for mono-microbial positive blood cultures (BC) processed using the BD Kiestra Work Cell Automation (WCA) system. Positive BC were processed by the WCA system by full-automatic subculture on solid media and digital imaging after 8 h of incubation (8-h method) followed by identification (ID) and antimicrobial susceptibility testing (AST). To evaluate the accuracy of the 8-h method, ID and AST from 8-h and overnight incubated colonies were compared for the same organisms. To evaluate its clinical impact, results from 102 BC processed by the 8-h method (cases) were compared with those from 100 BC processed by overnight incubation method (controls) in a comparable period. Identification after 8-h and overnight incubation gave concordant results in 101/102 (99.0%) isolates. Among a total of 1379 microorganism-antimicrobial combinations, categorical agreement was 99.4% (1371/1379); no very major error, 7 major errors, and one minor error were observed. TTR in cases (32.8 h ± 8.3 h) was significantly (p < 0.001) shorter than in controls (55.4 h ± 13.3 h). A significant reduction was observed for duration of empirical therapy (cases 54.8 h ± 23.3 h vs controls 86.9 h ± 34.1 h, p < 0.001) and 30-day crude mortality rate (cases 16.7% vs controls 29.0%, p < 0.037). Automation and 8-h digital reading of plates from positive BC, followed by ID and AST, greatly reduce TTR and shorten the duration of antimicrobial empiric therapy, possibly improving outcome in patients with mono-microbial bloodstream infections.
研究评估了使用 BD Kiestra 工作细胞自动化（WCA）系统处理的单一微生物阳性血培养（BC）对结果时间（TTR）和临床决策的影响。阳性 BC 通过 8 小时孵育后的全自动固体培养基传代和数字成像（8 小时方法）进行 WCA 系统处理，然后进行鉴定（ID）和抗菌药物敏感性测试（AST）。为了评估 8 小时方法的准确性，比较了相同生物体的 8 小时和过夜孵育菌落的 ID 和 AST。为了评估其临床影响，将 102 例 8 小时方法处理的 BC 结果（病例）与同期 100 例过夜孵育方法处理的 BC 结果（对照）进行比较。8 小时和过夜孵育后的鉴定结果在 101/102（99.0%）分离物中一致。在总共 1379 种微生物-抗菌剂组合中，分类一致性为 99.4%（1371/1379）；未观察到非常大错误，7 个主要错误和 1 个次要错误。病例组的 TTR（32.8 小时±8.3 小时）明显短于对照组（55.4 小时±13.3 小时）（p<0.001）。观察到经验性治疗持续时间明显缩短（病例组 54.8 小时±23.3 小时 vs 对照组 86.9 小时±34.1 小时，p<0.001）和 30 天粗死亡率降低（病例组 16.7% vs 对照组 29.0%，p<0.037）。自动化和阳性 BC 平板 8 小时数字读取，随后进行 ID 和 AST，可大大缩短 TTR 和抗菌经验性治疗持续时间，可能改善单一微生物血流感染患者的预后。
